I wouldn't add Date, Huber or Coetzer. Sure, they went deep in the odd Slam or two, but really they were only ever marginal top-10 players. Okay, so they may have hit a peak in or near the top-5, but that was due to a lack of depth at the time.
Mary Joe and Pam Shriver certainly.
In a similar vein, Sabatini, Martinez and Novotna each deserved more than 1 slam relative to their talent and other achievements. They just seemed to be constantly denied by either Graf, Seles, ASV, Navratilova or Hingis in the final stages.